Swing-jaw crushers



Aug. 11, 1959 L. R. FERGUSON SWING-JAW CRUSHERS Filed July 12, 1955 INVENTOR Lester R. Ferguson Y B wmgfiyw ATTORNEYS,

United States Patent SWING-JAW CRUSHERS LesterR. Ferguson, Riveredge, N.J., assignor to Kennedy- Van Saun Mfg. & Eng. Corp., New York, N.Y., a corporation of Delaware.

Application July 12,1955, Serial No. 521,554

3 Claims. c1. ans-237 My invention; relates to improvements in jaw crushers and more particularly to an improved shaft and bearing construction for supporting the swing jaws of jaw crushers.

Considerable difficulty and expense has resulted from the wear of the swingjaw, shafts of swing jaw crushers, particularly the. shafts of the larger swing jaw crushers. Much difiiculty has. always, been. encountered with large crushers where the swing jaw was bored out and the shafts inserted, because wear ofthe shafts always occurred no matter how solidly or how well the shafts were pressed'ino'rkeyed' to the swing jaw. In nearly all, if not. all, of these constructions, the wear on the shaft has beenzsuificient to: make it necessary to remove the swing jaw;. bone. it out anew and put in a larger shaft, or to build: up: thesh'aft by'weldiug it to fit the larger herein the swing jaw. l

A similar difiiculty has been encountered where the swing jaw shafts or stub shafts are cast integral with the swing jaw. 'For example, it was recently necessary to remove a swing jaw with worn shafts from a large swing jaw crusher and'ship it from South America to the manufacturers machine shop in'the United States in order to recondition the stub shafts.

Thefore'goingdifiiculties have not only caused considerable trouble but" have been'very expensive, not only for the, repairs themselves but because of the loss of. use

ofthe crusher during the repairs.

The primary object; therefore, of the present invention is; to solve the problem of. shaft wear with respect to wi riaw'qr sher hafls- A further object of the invention is to provide a construction which will avoid the foregoing difiiculties and expense resulting from the wear of swing-jaw shafts of swing-jaw crushers.

According to the invention, the foregoing difficulties and expenses are largely avoided by providing wear-resistant, readily-removable bushings on the swing-jaw shafts, either when the swing-jaw shafts are first made or when they are removed from the crusher because of shaft wear.

In a preferred construction, the wear-resistant bushings are advantageously fitted on shafts which are integrally cast with the swing jaws, the bushings being fixed to the shafts so that they are subjected to the wear occurring because of the swinging of the jaw.

The bushings are preferably made of hardened wearresistant steel and of sufficient length so that they extend respectively beyond the ends of the integral or other shafts, such extending portion being provided with a key slot for receiving a key extending across the end of the shaft and attached thereto by means of threaded studs.

When the bushings have been worn they may be readily replaced by new bushings without removing the heavy swing jaw from the crusher, it being only necessary to jack up the jaw, remove the bushing keys and bearing caps and slip out the worn bushings and replace them by new ones.

2,899,246 ZRatented, Aug. 11, 1959 eew 'An embodiment of:the invention is described more in detail thereinafter in connection with the showing, thereof presented in the accompanying drawings forming a part of this application.

In the drawingsz Fig. 1 is a vertical sectional view with parts broken away and omitted of a swing-jaw crusher embodyingv the invention;

' Fig. 2 isa broken perspective view of the movable jaw of the crusher shown in Fig. I, removed. from the crusher frame;

Fig. 3 is an enlarged broken vertical sectional view through one of the swing-jaw shafts embodying the construction of the present invention; and

Fig. 4 is a fragmentary end view showing the-end of the shaft and mounted bushing of Fig. 3.

According to the showing in Fig. 1, which illustrates the application of the invention to a heavy swing-jaw crusher, the crusher comprises a' frame including a pair of spaced side frame members 10; and an end frame member 12 against which a fixed crusher jaw 14 is mounted. The end frame member 12 is bolted to the side frame members by means of numerous bolts 16. The side frame members are tied together with heavy stay rods 18 located in back of a swing jaw 20 suspended by shafts between. the side frame members 10. In'the present: instance,. the swingv jaw 20 is. provided with integral shafts 22 at its upper end, oneon each side, which'are mounted in bearings in. the side/frame members 10. These bearings include the usual bearing caps 2.4. bolted onto the frame.

The swing jaw 20 is oscillated or swung by a conven tional'toggle operating mechanism, a portion of. which is. showntat 26.. ,A portion of the spring-biased tension rod28'isalso, shown.. f

The: present invention: is illustratedwith' respect to-' a heavy cast steel swinga jaw. provided with the integral hollow shafts 22.. The entire upper part of the head of the; swing: jaw- 20 is: hollow and the whole length" of the jaw includes hollow portions; as shown in Fig. 1 Theseheavy j aws are cast= in; this manner in order to. prevent or avoid; shrinkage strains. Fig. 2 illustrates the hollow upper portion of the jaw 20 and the; shafts x22, hi alii elwshws the-: s lpw. ns dw ann r-p rt of the jaw looking out through one of the hollow shafts 22.

It will be understood that when one of these jaws are used merely with the shafts 22, as shown in Fig. 2, these shafts will become worn particularly on their lower sides and through an angle developed by the amount of swing of the jaw. The shafts, therefore, wear out of round and soon break up the babbitts of the frame bearings. The present invention avoids these results in the manner described above. Accordingly, in building a new crusher, the shafts 22 are each provided with a sleeve bushing 30 preferably of hardened wear-resistant steel and of a length so that it extends somewhat beyond the end of the shaft 22, as shown in Fig. 3.

The bushings 30 are advantageously applied to the shafts 22 when the crusher is first built, but they may be applied to worn shafts, preferably after such shafts are machined or ground to a perfect round. However, in some instances, machining may be unnecessary. This method of repairing worn shafts is very inexpensive and may be done quickly and on the job.

The ends of the bushings 30, which project beyond the ends of the shafts 22 are provided with diametrically opposite slots or keyways 32, the bottoms of which are respectively flush with the ends of the shafts 22 or slightly beyond the ends of the shafts 22. The bushings 30 are held in place by metal keys or bars 34 having a length approximately equal to the outside diameter of the bushing 30 and which fit in the slots 32 and extend across hollow shaft 22. If the slots or keyways 32 are cut to a depth so that they are but slightly from 'the end of the shaft 22 when the inner end of the bushing 30 is'against the body of the swing jaw, the key or bar 34, when drawn up by the studs 36, will press the bushing 30 firmly against the body of the swing jaw at the base of the shaft 22. V V

The provision of the keyways and keys for the bushings frame and in which the swing jaw is provided with a 30 prevents relative rotation of the bushings with respect to the shaft 22 so that the shaft receives no wear at all. Therefore, as soon as the bushing 30 has worn 'somewhat, it may be readily replaced by a new bushing or reversed top for bottom so' that double wear' is obtained from a single set of bushings, in view of the fact that the lower portion of the bushing receives the greatest wear, since the lower portions of the bushings support the weight of the swing jaw, and the known fact that the jaw swings only through a relatively small angle. The swing jaws of swing-jaw crushers of the type disclosed herein swing through a relatively small angle as shown, for example, by British Patent No. 669,940.

In making the bushings 30 and providing their keyways 32 and keys 34, the length of the bushing projecting beyond the shaft 22 is correlated with the necessary thickness for the key 34 so that the keyway 32 is suificiently deep that the heads of the studs 36 do not project beyond the outer end of the bushing 30. As shown in Fig. 4, the key or bar 34 may be slightly shorter than the external diameter of the bushing 30.

While the invention has been illustrated in connection with heavy crusher jaws provided with integral hollow shafts, it is to be understood that the readily installed and readily replaceable bushings 30 may be ap- 1. In a swing jaw for a swing-jaw crusher having a shaft engageable in a bearing for suspending the swing jaw in the crusher frame, a readily-replaceable bushing on said shaft engageable in said bearing, said bushing projecting beyond the end of the shaft on which it is mounted, a slot in the projecting end portion of the bushing, a bar engaging in said slot and extending onto and crosswise of the end of the shaft, and means for releasably securing said bar to the end of the shaft for retaining thebushing on theshaft and preventing relative rotation between the shaft and bushing, whereby the bushing is adapted to take the wear instead of the shaft and be readily replaceable when worn.

2. In a swing-jaw crusher including a frame having side frame members each provided with a bearing for supporting a swing jaw and a swing jaw provided with shafts respectively engaging in said bearings and suspending the swing jaw in the frame between the side frame members, a readily-replaceable bushing on the portion of each shaft engaging in said bearings, each bushing extending beyond the end of the shaft on which it is mounted, diametrically positioned slots in the extending end of each bushing, a retaining bar extending across the end of each shaft and engaging in the slots of the bushing thereon, and means for releasably securing each bar to the end of the shaft with which it is associated for preventing relative rotation between the bushing and shaft.

3. A swing jaw as claimed in claim 1, wherein the swing jaw is arranged to swing through a relatively small angle on the shaft and in which said bushing is readily reversible top for bottom on the shaft when the bar is released with respect to the end of the shaft, whereby double wear is obtained from a single bushing because of the small angle of swing of the swing jaw.

References Cited in the file of this patent UNITED STATES PATENTS 274,159 Whiting Mar. 20, 1883 376,900 Morell Jan. 24, 1888 446,658 Buchanan Feb. 17, 1891 1,398,049 Swayze Nov. 22, 1921 1,774,159 Schmidt Aug. 26, 1930 1,851,109 Nye Mar. 29, 1932 2,582,516 Williams Ian. 15, 1952 FOREIGN PATENTS 407,245 Great Britain Mar. 15, 1934 669,940 Great Britain Apr. 9, 1952 kw rm. 

